Linux has a tweakable knob called laptop_mode which is meant as an energy saving tool for laptop users on battery: it basically says “try not to touch the disk for X minutes at a time, unless you really need to, and once you do, do everything that you’ve been piling up all at once”. It’s great for laptop users, and doubly so for things like my huge laptop with two 7200RPM HDDs. Seriously.

Now, there are two things that mean you “really need to” hit the disc: reading data that isn’t already cached (duh), and the fsync() and fdatasync() calls. The latter are requests by an application to ensure that all of the data written to far has hit the disc, and they cause the disk to spin up in laptop mode.

Unfortunately, Firefox has a habit of randomly issuing fdatasync() calls. It does this as part of the SQLite backend for its various databases (especially places.sqlite), in order to avoid data corruption. Now, data corruption isn’t terribly likely on a laptop with a battery (which is essentially a built-in UPS), so this is a terrible annoyance with little benefit anyway. There has been talk about this problem, but apparently it’s still around (and the toolkit.storage.synchronous about:config property didn’t work for me). Most of the reports appear to claim that this happens while browsing, but I’ve seen it happen periodically even when Firefox is left idle. Maybe it’s caused by some extension or AJAX webapp? Who knows.

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I’ll eventually write a longer post about how different bits and pieces of this laptop’s hardware fare under Linux. For now, I’ve managed to strike one of the more annoying issues: proper audio. Scroll down if you’re impatient and want the code; read on if you want the full story.

This laptop is peculiar because it has built-in “5.1″ audio. Yes, it does really have 6 speakers, though you’d be hard pressed to get much spatial separation out of them (and they aren’t even placed around symmetrically). However, the speakers do end up making a very decent multiway audio system, by laptop standards: the “rear” pair (which is actually between the keyboard and the screen; the mind boggles) is good with the high end, the “front” and center speakers (front edge of the laptop) are your average mediocre speakers that can handle mid-end, and the “Tuba” not-so-”sub” woofer fills in enough low-end to equal a decent overall speaker, although of course with zero stereo/spatial separation since there’s only one of it (actual subwoofers can pull off mono because the human ear can’t really hear spatial position at low frequencies, but the Tuba is more like the only non-sucky speaker in the entire laptop).

What this boils down to is that you really want good audio support for all 6 speakers if you want to take advantage of the audio capabilities at all. Most importantly, stereo needs to be upmixed and a good portion of the normal audio needs to be routed to the Tuba. ALSA’s asound.conf makes this easy, assuming the actual hardware works fine. Of course, that’s not the case.
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